Application Development frustration..

As someone trying to glue together various pieces of software to get some thing done..A.K.A Application developer, the most frustrating thing to do is reading up existing packages and learning their api interfaces…function names, arguments, format of arguments etc…

But what happens when you are calling some code you have written a month ago as part of the same application, and can’t remember the exact format of the arguments you assumed when designing that…
That’s infact a reliable sign of your capacity to design apis. i.e: you may be bad at designing api’s or interfaces….